Method of manufacturing terminal lugs



Oct. 25, 1960 B. DIBNER METHOD OF MANUFACTURING TERMINAL LUGS Filed May22, 1958 FIG. 3

I n. 1 I, I, z 1 "n w INVENTOR. 5524 fl/aA/ae nited States Patent METHODOF MANUFACTURING TERMINAL 'LUGS Bern Dibner, Wilton, Conn., assignor toBurndy Corporation, a corporation of New York Filed May 22, 1958, Ser.No. 737,068

2 'Claims. (Cl. 29-15555) This invention relates to the manufacture ofterminal lugs, and more particularly, to the manufacture of a pair ofelectrical terminal lugs having tubular barrel portions.

Previously, terminal lugs having tubular barrel portions weremanufactured by cutting off a predetermined length of seamless tubingand flattening one end. The flattened end became the terminal pad ortongue of the connector, and the tubular end was the conductor receivingportion. A hole was punched in the terminal pad or tongue for receivinga mounting screw.

In this prior art method of manufacture particular care had to be takenduring the flattening operation so that the transition section betweenthe flattened pad and the tubular body would not shear or tear.Moreover, there often would occur a drawback of metal from the top ofthe tubular body. In order to overcome these difiiculties, thetransition section had to be made excessively long, adding to the costof the connector and adding to its over-all length. In addition, the useof a double wall thickness for the terminal pad was wasteful of metal.Also, the minimum width of the terminal pad was determined by the sizeof tubing used in manufacture. In addition, when plating of the terminalwas necessary, there was always a danger that the plating acids would becaught up between the leaves of the flattened pad portion and causecorrosion.

One of the objects of my invention, therefore, is to provide a novelmethod of producing a pair of terminal lugs which is simple, economicaland fast.

Another object of my invention is to provide a novel method ofmanufacturing electrical connectors having a seamless barrel portion anda terminal pad of a thickness no greater than the wall of the barrelportion.

A further object of my invention is to provide a pair of electricalconnectors capable of being manufactured from seamless tubing with aminimum of scrap metal.

One of the features of my invention is the method by Which electricalconnectors have a seamless tubing barrel portion and a terminal lughaving a thickness equal to the wall of the barrel are manufactured. Mymethod contemplates starting with a tube of suitable material andcutting this tube into sections having a length approximately equal totwice the over-all length of a single terminal lug. This length oftubing then has two saw cuts made transverse to the axis of the tube andon opposite sides thereof and separated from each other approximately bythe desired length of the terminal pad. This cut section of tubing isthen flattened between the cuts and the edges of the fiat are cut intoto provide a pair of terminal lugs.

These and other features and objects of my invention will become moreapparent by reference to the following description taken in conjunctionwith the accompanying drawings in which:

Fig. 1 is a side elevational view illustrating the first step in mymethod of manufacturing terminals from a length of tubing;

Fig. 2 is a view in cross section taken along the lines 2-2 of Fig. 1;

Fig. 3 is a view in cross section taken along the lines 3--3 of Fig. 1;

Fig. 4 is a side elevational view illustrating another step in thepractice of my method of manufacturing terminals;

Fig. 5 is a view in cross section taken along the lines 55 of Fig. 4;

Fig. 6 is a perspective view of Fig. 4 illustrating still another stepof the practice of my invention;

Fig. 7 is a perspective view of a finished terminal lug made inaccordance with my invention; and

Fig. 8 is a view in cross section of the terminal shown in Fig. 7.

Referring to Figs. 1-3 of the drawing and in accordance with theprinciples of my invention, in order to manufacture a pair of terminallugs having a flat terminal pad portion and a barrel portion, it isnecessary to start with a mill length of seamless tubing from which apredetermined length 10 is cut. Two cuts 12 and 14 are made on oppositesides of the tubing 10 transverse to the longitudinal axis of the tubing10 and at a distance from each end which is approximately equal to thedesired length of the conductor receiving barrel portion 16 and 18 ofeach of the finished terminals. The portion 22 of the tubing 10 betweenthe cuts 12 and 14 is equivalent to the length of the terminal paddesired. In the next step in accordance with the method of my invention,the central portion 22 between the cuts 12 and 14 of the tubing 10 isflattened as shown in Figs. 4 and 5. This results in a double endedterminal having one conductor receiving body 16 having a central axisposition below the center line of the tongue portion 22 and anotherconductor receiving body 18 on the opposite end of the tube section 10and a central axis positioned above the center line of the tongueportion 20. Between these barrel receiving portions 16 and 18 is aterminal pad 22 having a thickness equal to twice the thickness of thewall of either barrel portion. Between the terminal pad 22 and each body16 and 18 at the location of the two cuts 12 and 14 there is a resultantneck portion 24 and 26. If it should be necessary to have a long neckportion 24 and 26 for specific mounting purposes, the saw cuts 12 and 14can be increased in width.

The next operation in accordance with the method of my inventionrequires the separation of the two terminal lugs. Referring to Fig. 6,the two dotted lines 28 and 30 along each edge of the tubular terminalpad 22 represent the cutting lines for the next step in the practice ofmy method which is a shearing operation in which the unitary edges 34and 36 of the tubular terminal pad are cut off resulting in a separationof the terminal pad. The cut off edges 34 and 36 are the only scrapmetal produced in the practice of my invention.

As shown in Fig. 7 each terminal has a terminal pad of a thicknessequivalent to the Wall thickness of the barrel portion or the wallthickness of the original tubing. A mounting hole 32 may be punched inthe terminal pad or otherwise provided. One easy method of accomplishingthis is during the shearing operation wherein the die may bespring-loaded to first punch the mounting hole through the double padand then shear along the lines 30 and 28. If the terminal pad of theresulting tongues is desired to be narrower than the diameter of thetube, it is possible for the shearing lines 28 and 30 to be moved closerto the center of the terminal lug, thus narrowing the pad section. Itcan thus be seen that by this method of manufacture, terminal lugs withtubular barrel receiving portions can be made at an extremely fast rateof production, since pairs of terminals are produced instead of singleterminals as in previous methods. Moreover, due to this method,

the terminal pads need not have excessive width or thickness resultingin a saving of-metal. The corrosion hazards from retained acids duringthe plating operation is eliminated. Moreover, narrow terminal padsmaybe provided and a'minimum' of scrap results from the manufacture inaccordance with my invention;

i lt is, of course, obvious that a single terminalcan be produced bythis method rather than the production of a pair-of terminals describedabove. To produce a. singleterminal, it is merely necessary to make'asaw cut in the wall 'of'the tube transverse to'thecentral axisand thenflatten the tube to one side of the saw cut, 'After flattening the tube,shearing the edges of the flattened portionwill yielda single terminalhaving aseamless barrel'portion and aterminal portion having a lengthequal to the flattened portion and 'a thiekness equal to thethicknessfio'f the Wall of the starting tube material.

I have thus described my invention, but I desire it understood that itis'not confined to the particular forms or uses shown and described, thesame being merely illustrative, and that the invention may be carriedout in other Ways without departing from the spirit of my invention,and, therefore, I claim broadly the right to employ all equivalentinstrumentalities coming within the scope of the appended claims, and bymeans of which, objects of my invention are attained and new resultsaccomplished, as it is obvious that the particular embodiments hereinshown and described are only some of the many that can be employed toattain these objects and accomplish these results.

I claim: 7 r

l. The method of manufacturing a pair of terminals comprising the stepsof cutting a pair of saw cuts on opposite sides of a predeterminedlength of tube, said cuts spaced from each other and transverse to thecentral axis of said tube said saw cuts being made to a depth at leastequal to the radius of said tube; flattening the portion of said tubebetween said saw cuts and shearing off the edges of said flattenedportion by making cuts intersecting said saw cuts. 7

2. The method according to claim 1 which further includes the step ofpunching a hole in said flattened portion to produce a mounted hole ineach of said pair of terminals.

' References Cited in the file of this patent V UNITED STATES PATENTS910,684 Horner Ian; 26, 1909 1,391,792 Recker Sept. '27, 1921 2,371,469Rogofl Mar. 13, 1945 2,511,806 Macy June 13, 1950 UNITED STATES PATENTOFFICE CERTIFICATE- OF CORRECTION Patent No 2 957 226 October 25 1960Bern- Dibner It is hereby certified that error appears in the abovenumbered patent requiring correction and that the said Letters Patentshould read as corrected below.

Column 4', line 17 for "mounted" read mounting a Signed and sealedthisd'ith day of April 1962 (SEAL) Attest: I

ESTONH e. JOHNSON 1 I DAVID L. LADD Attesting Officer J Commissioner ofPatents

